Cap assembly



Jan. 29, 1963 K. s. AKEHURST CAP ASSEMBLY Filed July 3, 1959 INVENTOR. KENNETH 5 'AKEHURS T BY x224 aw AT TOPNEVS United States Patent Ofitice 3,075,451 Patented Jan. 29, 1963 3,075,451 CAP ASSEMBLY Kenneth S. Akehurst, Castro Valley, Califl, assignor to Noll Manufacturing Company, Berkeley, Calif, a corporation of California Filed July 3, 1959, Ser. No. 824,886 1 Claim. (Cl. 98-46) My invention relates to devices especially useful in the construction industry for use on building roofs to surround the emergent vent pipes which normally extend above the roof. The device is particularly concerned with installations on roots which have diflerent pitches on different jobs so that the same unit can be shipped in separate parts, can readily be installed in the field and can there be easily and permanently set into final position by ordinary workmen.

A device of this general sort is shown in Patent No. 2,890,642 issued to Fernsten et al. on June 16, 1959, entitled Cap Assembly.

One of the objects in a device of this nature is to provide a firm support for the upper portion of the structure which does not necessarily engage the upwardly projecting vent pipe and to do so without the use of extra braces, guy wires and the like. It is necessary to provide an angular adjustment and one which can be set at any degree within narrow limits by an ordinary artisan in the field, yet which when set will remain in set position despite dislodging forces, such as high winds, snow load and the like.

Another object of the invention is to provide a cap assembly which can easily be adjusted, yet is simple and economical to fabricate, can readily be shipped and stored and as easily erected.

A still further object of the invention is to provide a cap assembly which. will hold its setting against dislodging forces for an indefinite time, yet can easily be dismantled if necessary.

Other objects, together with the foregoing, are attained in the forms of the invention described in the accompanying description and illustrated in the accompanying drawing, in which:

FIGURE 1 is a front elevation of one form of cap assembly constructed in accordance with the invention.

FIGURE 2 is a side elevation of the device of FIGURE 1, certain portions of both figures being broken away to reduce their size.

FIGURE 3 is a side elevation comparable to FIGURE 2 but showing a modified form of the invention, portions being broken away to reduce the figure size.

In the form of structure particularly shown in FIG- URES l and 2, the installation is preferably made on a roof 6 having a slope and having a vent pipe 7 projecting upwardly therefrom approximately on a first axis 8. Installed on the roof is a sheet metal base plate 9 substantially rectangular in plan and having a central opening for passing the pipe 7. Upstanding from the base plate 9 is a base cone 11 conveniently fabricated of somewhat flexible sheet metal, such as galvanized iron of about twenty-two gauge. The cone 11 is suitably secured to the base plate 9 and when in position on the roof is substantially symmetrical about a second axis 12 which is approximately, although not exactly, coincident with the first axis 8.

Encompassing the pipe 7 and telescoped with the base cone 11 is a substantially circular cylindrical tube 13 also fabricated of similar sheet metal and having a circular lower edge 14 resting upon the base cone 11.

Overlying the base cone 11 and the tube 13 are straps 16 and 17 fabricated conveniently of flexible metal and disposed at the ends of a diameter of the cone and of the tube. The lower ends of the two straps are preferably secured to the cone by rivets 18 and 19 and thus are permanently and firmly afiixed thereto so that the straps are relatively immovable except as they may be bent. Each of the straps is preferably formed with a central elongated slot 22; extending from a point adjacent the rivets 18 and 13 to the other end of the strap.

The tube 13 at the opposite ends of a diameter is provided with fixed bolts 23 and 24 having heads 26 either tightly engaging the material of the tube or permanently secured thereto. The bolts 23. and 24 project diametrically outwardly from the tube 13 and pass through the slot 22. between the sides of the adjacent straps. On the threaded bolts there are provided wing nuts 27 and 28. These either have large enough bases to span the straps or can be provided with intervening washers.

In the use of this form of the device, the base cone 11 is situated at an appropriate angle to abut the roof and to encompass the vent pipe 7. The straps 16 and 17 are bent outwardly and the tube 13 is lowered over the vent pipe 7 until its lower edge 14 rests upon the subjacent material of the base cone. The wing nuts 27 and 28 not yet having been installed, the straps 16 and 17 are bent so that they lie closely adjacent to the tube 13 and with the bolts 23 and 24 projecting through the slots 22.

The nuts 27 and 28 are installed with a light tension until such time as the tube 13 is precisely lined up and brought into its final position. At that time, the nuts 27 and 28 are tightened. This not only holds the tube 13 on the conical base against rocking in the plane of the bolts but there is likewise also sufiicient frictional interengagement between the straps and the tube when the nuts are tightened to prevent the tube rocking laterally in a plane transverse to the plane of the bolts. In this way, the tube is firmly held in position indefinitely, although it can be removed when desired by a reversal of the described steps.

In the form of the structure shown in FIGURE 3, the base 31 is generally constructed as previously described, as is the telescoped and superposed tube 32. In this instance, however, the strap 33, which is afiixed to the base 31 by rivets 34, extends upwardly and overlies the tube 32. The strap adjacent its outer free end is provided with a lip 36 for easy finger engagement and is likewise provided with a corrugation 37 intended to interengage with any one of a series of lugs 38 formed by outward projections struck from the material of the tube 32 in appropriate locations substantially on a diameter thereof. When the tube 32 is rocked with respect to the base 31 into any one of three positions, the respective one of the lugs .38 is engaged with the corrugation 37. The material of the strap 33 is relatively stiff and springy so that a snap interengagernent is had, effective permanently, although releasable by superior force exerted by a workman.

A very similar arrangement is provided at the other end of the diameter on which the strap 33 is disposed except in inverted order. In fact, both fasteners utilized can be upright, both can be inverted or one can be upright and the other inverted, as shown in FIGURE 3.

The strap 41 of stiff, springy material is connected by rivets 42 to the tube 32 and not only overlies the subjacent material of the tube but also extends downwardly to overlie the subjacent material of the base 31. In this variation, the material of the base 31 is provided with a number of lugs 43 struck outwardly from the base material. Any one of the lugs 43 can be engaged by a corrugation 44 on the springy strap 41. A lip 46 is provided for finger engagement by the workman.

In the assembly of this device, after the base cone 31 has been positioned, it is merely necessary to lower the tube 32 axially downwardly until such time as the lower edge 47 of the tube 32 abuts the material of the cone 31. The slope of the roof being appropriate, the finger lips 36 and 46 ride over the successive lugs, such as 38 or 43, and the springy straps 33 and 41 yield and return until the parts are spring-locked in final engagement. If the pitch of the roof is changed or the orientation of the structure is to be varied, it is merely necessary to rock the tube 32 so that other lugs interengage with the corrugations.

While this form of device does not provide an infinite number of adjusted positions, it does provide a number of adjusted positions in many instances sufficient to accommodate most of the buildings on which the cap assembly is to be utilized. By making the lugs 38 and 43 of sutficient circumferential or lateral extent and by making the straps 33 and 41 of substantial width and considerable stiffness, the lugs and corrugations interengage well enough so that not only is the tube stable in a fore and aft direction (along the slope of the roof) but also is quite stable in a transverse direction and resists dislodging forces such as are due to wind or snow.

With the form of device shown in FIGURE 3 also, in the event it is necessary to change the tube 32 for any reason or to gain access to the interior, it is not always necessary to spring the straps 33 and 41 outwardly by engagement with the lips 36 and 46 but the tube 32 can be rotated through a portion of a circle to provide disengagement of the otherwise interlocked parts. A reversal of this rotating motion also will lock the parts together. This is a variation of the technique of simply forcing the tube 32 downwardly into engagement with the base.

What is claimed is:

A cap assembly comprising a frusto-conical sheet metal base,

said base having a first cone element and a second cone element diametrically opposite said first cone element,

a substantially circular-cylindrical sheet metal tube separate from and positioned over said base,

said tube having a first cylinder element and a second cylinder element diametrically opposite said first cylinder element,

said tube also having a substantially circular edge in contact with said base and rockable on said base away from and into a position in which all of said elements lie in a single plane,

a single pair of elongated flat straps relatively flexible in the direction of their thickness and relatively inflexible in the direction of their width and consisting of a first strap and a second strap,

4 said first strap being disposed to lie with its width against the outside of said frusto-conical base along said first cone element and being flexed in the direction of its' thickness within the elastic limit thereof also to lie with its width against the outside of said tube along said first cylinder element when said tube is in said position, means for fixing one end of said first strap to said frusto-conical base,

means defining an elongated first slot in said first strap adjacent the other end thereof and extending in the direction of the length of said first strap,

a first screw fastened to said tube and passing through said first slot,

a first fastener on said first screw and movable to clamp said first strap in flexed position against said tube in any position of said first screw along said first slot,

said second strap being disposed to lie with its width against the outside of said frusto-conical base along said second cone element and being flexed in the direction of its thickness within the elastic limit thereof also to lie against the outside of said tube along said second cylinder element when said tube is in said position,

means for fixing one end of said second strap to said frusto-conical base,

means defining an elongated second slot in said second strap adjacent the other end thereof and extending in the direction of the length of said second strap,

a second screw fastened to said tube and passing through said second slot,

and a second fastener on said second screw and movable to clamp said second strap in flexed position against said tube in any position of said second screw along said second slot.

References Cited in the file of this patent UNITED STATES PATENTS 

